Combine soy sauce, broth, brown sugar, garlic, and ginger in a small mixing bowl. Place half of the mixture in a gallon-sized Ziploc bag, add sliced beef, seal (pressing as much air out as you can), and refrigerate for at least 2 hours.
Add cornstarch to remaining mixture in bowl and stir until smooth, cover and refrigerate until ready to use.
Prepare linguini noodles according to package directions. While noodles are cooking, heat 2 teaspoons oil in a large skillet over medium-high heat and add steak slices, discarding excess marinade. Stir-fry until just browned, remove steak from skillet and set aside.
Add remaining oil to the same skillet and stir-fry peppers, onion, carrots, and broccoli until onions become clear and soft. Add cabbage and beef to the skillet and cook until cabbage becomes soft.
When noodles are done cooking, drain and toss with beef/vegetable mixture, adding the reserved sauce mixture. Toss until noodles are coated in sauce. Top with sesame seeds and/or red pepper flakes (optional) and serve immediately.
Please note that the prep time and cook time on this recipe does not include the 2+ hours of time needed to marinate the beef.